Improved process of forming smooth tops on glass jars



liuitmi gitanas @sind (utilita FREDERIGYKVROHRBAGDER AND F'ERDINAND'ioniualvr,'0F PHILADELPHiA, PENN- i SYLVANIA, AssiGNons To SALMON B. ROWLEY, cn SAME PLAGE.

Letters Patent No. 106,624, rlatcll August 23, 1 ;870.

IMPROVED PROCESS OF FORMING SMOOTH TOPS ON GLASS JARS.

The Schedule referred to virr these Letters Patent and making part of the same We, FREDERICK RoHRBAcHEu and- FERDINAND HORMANN, of Philadelphia, county of Philadelphia,

Siate of Pennsylvania, have invent-ed an Improve ment in Glass Jars, and in a process of ibrming'smooth tops for the same, of which the following is a specification.

Nata-rc and ly'cct of the Invention..

l A This invention consists;-

`First, of a mode or process, hereinafter described,

ot' forningfon the extreme upper end of'a glass its extreme upper end, in an entirelyungrou'nd blown bearing surface for receiving a packing ring.-` Y Thirdly, of a glass jar, having, at its upper end,;a

ing-ring from the contents of the jar.

Descriptioaof` the Accompanying Draw-illy;l 'for A Figure 1 illustrates thcprocess of forming smoothblowu tops for glass jars, and shows the jar as it appears before being operated on. r

Figure 2' showsfthe glass jar complete, with pack--` ing-ring, cover, and fastener.

General Description. In blowing glass jars in molds, there isialways an uor'erblowras it is termed, that is, ajthin, hollowv protuberance, which, afterthe jar has 4been blown and annealed, is struck oli". A ragged projection,'how-` ever, the remnant of this overblon', alwaysremains on the jar, and this must be removed before the jar is saleable.

It4 will he observed that the jar illustrated in the .drawing 'has an internal'lip, h, and it is from the. iiinel* edge ot' this lip that the overblowV takes its rise.

The ragged remnant of this overblow -we do uotresary is to hold the jar in the position seen in g. `1., and then 'move the grinder forward until 1t has penetrated the mouth of the jar far-enough to remove vthereinnant f ofthe overblow. The result will he that sh0\,v.n iln;1,ig. 2, a perfectly true bearing, a, on the extreme upper end of the jar; and this bearing, having the natural smooth surface of the glass, is superior to a ground surface.

It may be remarked that, in blowing the jar in the mold, the truth of the bearing surface a is always determined.

In fig. 2

B is the rubber-ring;

D is the cover, made of glass in the present instance; and

E, :a yoke, theV bent endsv of which are arranged to catch beneath the inclined projections, c, on the neckv ot' thejar. Y

In -ordinary jars the inner edgeof tb.e month is never exactly circular, and, consequently, a circular projection, such as that on the under sident' the cover 1), cannot fit so tightly as to prevent the contents of the-jar from gaining access to the' rubber packing,

but, by reducing the inner edge of the lip h substantially as described, it must be, necessarily, l so true that the projection on vthe under side of the cover will t snugly enough in it to isolate the rubber-ring from thecontents of the jar.

,o lIt should be understood that our invention isv in no way-connected with any specitic cover or fastening.

` Claims.

l. Themode or process, substantially t s described, of forming, on the extreme upper en d of a glass jar, asinooth surface for receiving'a pacliing-ring.

2. A mold lblown"glass jar, terminating at its extreme upper end in an entirely nnground, lblown surface, for the packing-ring.

3. A glass jar, having, at its upper end, a blown lip, the inner edge of which is`ground or reduced, in combination with a cover, having a circular project-io adapted to the mouth.

In testimony whereof we have signed our names to this specification in the presence of two subscribing witnesses.

FREDK. ROHRBACHER.

, FERDINAND HOItMANN.

Witnesses F. B. RICHARDS, HARRY SMITH. 

